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Bethany can mow her family’s lawn in 4 hours. Her brother Colin can mow the lawn in 3 hours. Which equation can be used to find x, the amount of time it would take for Bethany and Colin to mow the lawn together?.

User Dan Bracuk
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2 Answers

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4÷×=3 because 4×3=12 so do the opposite and so ÷and u do 4÷x=3
User Biffen
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Answer:

The required equation is
(1)/(4)+(1)/(3)=(1)/(x)

The amount of time it would take for Bethany and Colin to mow the lawn together is approx 1.71 hours.

Step-by-step explanation:

Given : Bethany can mow her family’s lawn in 4 hours. Her brother Colin can mow the lawn in 3 hours.

To find : Which equation can be used to find x, the amount of time it would take for Bethany and Colin to mow the lawn together?

Solution :

Let the whole lawn of the house be 1 unit.

Bethany can mow her family’s lawn in 4 hours.

i.e.The rate of Bethany is
(1)/(4) lawns per hour.

Her brother Colin can mow the lawn in 3 hours.

i.e.The rate of Colin is
(1)/(3) lawns per hour.

Together they work x hours.

i.e. The together rate is
(1)/(x) lawns per hour.

So, The equation form according to question is


(1)/(4)+(1)/(3)=(1)/(x)

Therefore, The required equation is
(1)/(4)+(1)/(3)=(1)/(x)

Solving for x,


(3+4)/(4* 3)=(1)/(x)


(7)/(12)=(1)/(x)


x=(12)/(7)


x=1.71

The amount of time it would take for Bethany and Colin to mow the lawn together is approx 1.71 hours.

User Dinesh Kandpal
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